Subsea torque tools are required to perform a range of tasks on subsea infrastructure and equipment, for example applying torque to actuate rotating components of valves, or to lockdown or release clamps on equipment for the oil and gas industry. Typically, these rotating components are designed to be actuated at a specific torque, and when required to rotate a subsea component, an operator of an ROV torque tool will choose the correct socket size and apply the appropriate torque so that the tool does not impart a torque greater than the maximum capability of the subsea component. The component may fail or become damaged if the torque applied to it by a torque tool is excessive. The retrieval of the subsea component for repair or replacement can be difficult and expensive.
The range of tasks that an ROV torque tool is required to perform means that the torque output of the tool must be changed depending on the torque requirements of the task. The changing of socket sizes on the ROV torque tool has previously been achieved by using external change-out modules to change between sockets of different sizes. However, this method can be cumbersome and time-consuming.
More recently, ROV torque tools have been developed in an effort to avoid relying on external change-out modules and to reduce the delays and costs involved in changing the gearbox and/or motor. These tools have spring-loaded nested sockets which can switch between sockets of different sizes, depending on the application.
However, spring loaded nested sockets have the disadvantage that when the torque tool socket is docked onto a subsea structure component, it is not clear which socket size is being used. If an incorrect socket size is used it may result in the wrong value of torque being applied to the subsea structure component and result in significant damage to the subsea structure and the torque tool.